Preseason Position Reviews: Running Back

The Pac-12 features another strong crop of running backs -- seven return after compiling more than 900 yards rushing in 2011 -- but there are also a few teams facing uncertainty at the position.
Evaluations aren't easy here. A number of teams have an A-list leading rusher back but uncertain depth. Others have plenty of experience returning but no proven A-lister. So stars and depth matter here...